Minerals in Unrefined Salt

Sea salt is collected from bodies of saltwater.

Unrefined salt is made from seawater and is minimally processed -- typically by natural evaporation, but also by gentle heating or roasting. Compared to refined table salt, unrefined sea salt is exposed to less or no chemical treatment, which leaves behind the natural minerals found in seawater. Consequently, sea salt contains many more minerals, although not as much iodine compared to iodized table salt. Unrefined salt can be contaminated with impurities such as mercury, so choosing a reputable brand is important.

Salt Processing and Composition

Most refined table salt is mechanically harvested from salt mines then treated chemically to remove all the impurities, which also includes the minerals. The salt is then heated under high compression to get rid of all the moisture. What’s left behind is very pure, fine white crystals consisting of almost 61 percent elemental chloride and about 39 percent elemental sodium. In contrast, most unrefined sea salt is produced by natural evaporation of seawater or water from salty lakes and then collected and minimally processed to produce relatively pure sodium chloride, but not as pure as table salt. Dr. David Brownstein, a holistic family physician, states that sea salt typically contains significantly less chloride, but more minerals, trace elements and moisture, which gives sea salt more flavor and color.

Main Minerals

The main minerals in unrefined sea salt -- in addition to chloride and sodium -- are magnesium, sulfur, potassium, calcium and bromine, which match the mineral composition of seawater. Unrefined salt also contains dozens of other minerals and elements, but only in very small or trace amounts. All these additional minerals and elements are removed from refined table salt. It’s the presence of these minerals, many of which act as electrolytes in the body, that give sea salt a reputation of being healthier than refined table salt. However, Katherine Zeratsky, a registered dietician with the Mayo Clinic, states that sea salt and table salt have the same nutritional values, despite the fact that sea salt is usually marketed as more natural, and the most notable differences are simply taste and texture.

Iodine

Iodine is also considered a mineral and it’s found in unrefined sea salt, but iodized table salt contains considerably more of it. The Salt Institute states, “Although often promoted as a more healthful alternative to refined table salt, natural sea salt has little iodine and is a poor choice for those concerned about ensuring their iodine sufficiency.” A lack of dietary iodine leads to thyroid gland dysfunction and goiter, or inflammation of the thyroid. Goiter was much more common in the United States many decades ago until government initiatives forced manufacturers to iodize their salt.

Mineral Removal

The main reasons why minerals and other elements are removed from table salt include increased purity, extended shelf life, cleaner, whiter look and less clumping due to moister accumulation. The overall mineral content in sea salt, aside from sodium and chloride, is relatively low and shouldn’t be relied on as a significant dietary source. If you want to increase your intake of minerals, eat foods such as fish, dairy products, leafy greens and legumes or consider taking a multi-mineral supplement.

About the Author

Johnathon Andrew obtained his M.Sc. from the University of British Columbia in 2003 and then went on to complete his Medical Degree at Queen's University in Kingston. He has been published in numerous peer-reviewed journals such as the "Journal of Manipulative and Physiological Therapeutics" and the "Canadian Journal of Neurological Sciences."